Q: I’m dating an amazing new boyfriend, but I just can’t let go of old feelings I have for my ex, and can’t help talking (ok, flirting) with him.

You know how Marilyn Monroe once said that things fall apart so that better things can fall together? That’s this situation. You need to give yourself a chance to let something fall apart, so you can focus on the next, better thing.

In other words, block your ex on Snapchat.

If we’re being honest here, it’s definitely exciting when you start things with a new guy, but sometimes there’s all this crazy ridiculous insecurity that comes with it. You keep thinking things like, Is it going to work out? Or is it going to crash and burn after I get a giant zit on my face? So feeling sentimental about an ex is totally normal because it gives you a sense of security—it’s your familiar safety blanket while you navigate new territory. But it’s not fair to anyone—not your boyfriend, not your ex, not yourself. You really can’t be 100% in a relationship until your feelings are 100% ready for him (or at least 90%, with 10% reserved for Dave/James Franco or Liam/Chris Hemsworth). And as for your ex, you’re just stringing him along. So move on. Get closure. Be upfront and tell him that you really like this new guy, and that you need to give yourself the chance to try a relationship with this amazing new boyfriend of yours. You can still talk to your ex—no one can tell you whom you can and can’t talk to, obvi—but only if you know that you aren’t leading anyone on or rehashing old emotions. It takes time to get to that point, and if it means you have to delete his number/block him on social media/make a list of all the reasons he’s your ex, then by all means go for it.

Unless your ex is Dave/James Franco or Liam/Chris Hemsworth, in which case, do not block him on Snapchat.